Various sensors such as gas sensors (e.g., an oxygen sensor and an NOx sensor), a temperature sensor, and a knock sensor are mounted on a vehicle. Such in-vehicle sensors are connected to a communication bus constructed in the vehicle, and are controlled, in a centralized manner, by an ECU (electronic control unit) connected to the communication bus. Therefore, each in-vehicle sensor has an identifier which is assigned thereto and is used for identifying the sensor in communications through the communication bus. The ECU exchanges communication data with each in-vehicle sensor through the communication bus by designating the identifier.
Notably, examples of standards for such a communication bus include CAN (Controller Area Network) and LIN (Local Interconnect Network).